A.under water, “τὴν δ᾽ ἄνεμος . . καὶ κῦμα θαλάσσης θῆκαν ὑποβρυχίην” h.Hom.33.12; ὑποβρύχιον . . φέρων (sc. τὸν ἵππον) Hdt.1.189; “ὑ. θάνατοι” Cat.Cod.Astr.2.161: metaph., “ἡ Ἑλλὰς ὑ. φερομένη” Aristid.Or.23(42).46.
II. below the surface, “ὑποβρύχιαι συμπεριφέρονται” Pl.Phdr.248a; opp. ἐπιπολάζων, Luc.Dips.3; deep-seated, “ἐκπυήσιες” Hp.Art.12; ὑ. πυρετός a hidden fever, one that shows itself by degrees, Id.Epid.1.25 (so Littré with Gal.9.560; ἄρχεται μαλακῶς καὶ ὑποβρύχια [Adv.] codd., Kühl.); “πυρετοὶ -ιοι” Aret.SD2.9; ὀφθαλμῶν ὑ. πόνος ib.1.2; “πῦρ” Id.SA2.7.
III. = ὑποβρυχώμενος, of oxen, h.Merc.116.